Shown with a cast-on count of 25 stitches.  

• Rows 1, 3, 5, 7, 9, and 11 (WS): Purl.
• Row 2: K1, *yo, k2, sl1-k2tog-psso, k2, yo, k1, repeat from *.
• Row 4: K2, *yo, k1, sl1-k2tog-psso, k1, yo, k3, repeat from * to last 7 sts, yo, k1, sl1-k2tog-psso, k1, yo, k2.
• Row 6: K3, *yo, sl1-k2tog-psso, yo, k5, repeat from * to last 6 sts, yo, sl1-k2tog-psso, yo, k3.
• Row 8: K1, k2tog, k1, *yo, k1, yo, k2, sl1-k2tog-psso, k2, repeat from * to last 5 sts, yo, k1, yo, k1, k2tog, k1.
• Row 10: K1, k2tog, *yo, k3, yo, k1, sl1-k2tog-psso, k1, repeat from * to last 6 sts, yo, k3, yo, k2tog, k1.
• Row 12: K2tog, yo, k5, yo, *sl1-k2tog-psso, yo, k5, yo, repeat from * to last 2 sts, k2tog.